diff --git a/dbms/src/Storages/KVStore/Read/ReadIndexDataNode.cpp b/dbms/src/Storages/KVStore/Read/ReadIndexDataNode.cpp
index 7d5211b9745..f141ec9b28e 100644
--- a/dbms/src/Storages/KVStore/Read/ReadIndexDataNode.cpp
+++ b/dbms/src/Storages/KVStore/Read/ReadIndexDataNode.cpp
@@ -82,7 +82,7 @@ void ReadIndexDataNode::runOneRound(const TiFlashRaftProxyHelper & helper, const
                 e.second->update(history_success_tasks->second);
             }
 
-            LOG_TRACE(
+            LOG_DEBUG(
                 DB::Logger::get(),
                 "[Learner Read] Read Index in Batch(use histroy), max_ts={} region_id={} waiting_tasks={} "
                 "running_tasks={} histroy_ts={}",
@@ -123,7 +123,7 @@ void ReadIndexDataNode::runOneRound(const TiFlashRaftProxyHelper & helper, const
                 }
             }
 
-            LOG_TRACE(
+            LOG_DEBUG(
                 DB::Logger::get(),
                 "[Learner Read] Read Index in Batch(new request), max_ts={} region_id={} waiting_tasks={} "
                 "running_tasks={} should_build_running_task={} build_success={}",
@@ -253,6 +253,7 @@ void ReadIndexDataNode::doAddHistoryTasks(Timestamp ts, kvrpcpb::ReadIndexRespon
         }
     }
     {
+        LOG_DEBUG(DB::Logger::get(), "[Learner Read] Add histroy tasks ts={} region_id={}", ts, region_id);
         history_success_tasks.emplace(ts, std::move(resp)); // move resp
     }
 }
diff --git a/dbms/src/Storages/RegionQueryInfo.h b/dbms/src/Storages/RegionQueryInfo.h
index 66f74f38d71..db527bee2b3 100644
--- a/dbms/src/Storages/RegionQueryInfo.h
+++ b/dbms/src/Storages/RegionQueryInfo.h
@@ -72,14 +72,26 @@ struct MvccQueryInfo
 
     // A cache for Region -> read index result between retries
     using ReadIndexRes = std::unordered_map<RegionID, UInt64>;
-    ReadIndexRes read_index_res_cache;
 
     DM::ScanContextPtr scan_context;
 
+private:
+    ReadIndexRes read_index_res_cache;
+
 public:
     explicit MvccQueryInfo(bool resolve_locks_ = false, UInt64 start_ts_ = 0, DM::ScanContextPtr scan_ctx = nullptr);
 
-    void addReadIndexResToCache(RegionID region_id, UInt64 read_index) { read_index_res_cache[region_id] = read_index; }
+    void addReadIndexResToCache(RegionID region_id, UInt64 read_index)
+    {
+        LOG_DEBUG(
+            DB::Logger::get(),
+            "addReadIndexResToCache region_id={} read_index={} start_ts={}",
+            region_id,
+            read_index,
+            start_ts);
+        read_index_res_cache[region_id] = read_index;
+    }
+
     UInt64 getReadIndexRes(RegionID region_id) const
     {
         if (auto it = read_index_res_cache.find(region_id); it != read_index_res_cache.end())